Mastering The Cannabis Seedling Stage In Just 3 Steps - RQS Blog (2023)

Three simple steps to mastering the cannabis seedling stage.


  1. Step 1: pick the right genetics, containers, and medium for your seedlings
  2. Step 2: use the right germination techniques
  3. Step 3: mastering the seedling stage
  4. How to water your cannabis seedlings
  5. How to prevent damping off
  6. How to avoid nutrient problems
  7. How to prevent pests and bugs
  8. How to prevent stretchy seedlings
  9. Know when and how to transplant your seedlings
  10. Bonus step: understanding the seedling stage
  11. Get growing!

Cannabis seedlings can be tricky to keep alive, especially for rookie growers. With a solid understanding of seedlings and their requirements, though, the all-important seedling stage can be a lot less threatening. Keep reading for three simple steps to growing healthy seedlings.

Step 1: Pick the Right Genetics, Containers, and Medium for Your Seedlings

When sourcing your seeds, be sure to actively search outthe right strain for you; your experience and skill as a grower, budget, grow equipment, preferences in taste and effect, and whether you’regrowing indoorsoroutdoorswill determine which strain will yield the best results for you.

As for themedium, we always recommend growing in a light, well-aerated, slightly acidic soil with apH of 6.3–6.5.We recommend using between 20–50% perlite in your medium to aid with soil aeration and nutrient retention. The more nutrients you plan to give your plants, the more perlite you should add to your soil to help with drainage and prevent nutrient lockout.

Remember to water just around the stem of your seedlings, andonly once the soil has completely dried out(see the section on over/underwatering below for more info). Also, keep in mind that seedlings (especially autoflowering varieties) areextremely sensitive to nutrients.Never plant them into hot (nutrient-rich) soil and don’t start feeding them until they’ve grown 3–4 sets of true leaves.

When it comes to picking pots, we recommend the following approaches for autoflowering and feminized seedlings.

The Right Pots for Autoflowering Cannabis Seeds

Whengrowing autoflowers, we recommend planting them directly in their final pots. Because of their short life cycle, it’s best to avoid putting autoflowering strains through any kind of unnecessary stress, includingtransplanting. While the exact pot size you use will vary depending on the strain you’re growing and the size of your grow space,most auto growers use pots between 5–15l.

The Right Pots for Feminized Cannabis Seeds

If you’re growing feminized seeds, transplanting isn’t as much of an issue since these plants have time to recover from the stress. UsingEasy Startgermination pots, you can support robust health right from the beginning. You’ll want to transplant your seedlings just before they start outgrowing their starter pots. We typically recommend transplanting once they’ve grown sets of true leaves that spread out to cover the full circumference of their current container.

From here,most indoor growers move their plants directly into 12l pots,but you can go above or below that to suit your particular strain and grow setup. Keep in mind that you can (and should) up-pot feminized photoperiod plants a few times to max-out development, meaning you don’t need to transplant your seedlings into a giant pot right away.

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A Note on Cannabis Pots

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From cheap nursery containers to sophisticated smart pots, growers are spoilt for choice when it comes to picking the right container for their cannabis plants. And while it’s possible to grow great weed in cheap plastic propagation containers, there are a couple of things you’ll want to keep in mind when choosing pots for your weed plants.

1. Drainage holes

Make sure your pots drain well to protect your plants against fungal pathogens and root rot. If your pots don't already contain holes (or some other kind of mesh to allow runoff), you'll need to puncture them yourself.

2. Aeration

One of the functions of a plant's substrate is to serve as a site for air exchange between the roots and the environment. Smart pots like theRQS Fabric Pothelp your plant’s roots respire by allowing more oxygen to reach them. This translates into faster, more vigorous growth, healthier plants, and a better harvest.

3. Pot size

Keeping tiny seedlings in huge pots increases the risk of overwatering, as your plant’s roots won’t be big enough to extract all the water from their substrate. Any water that stays in the substrate will effectively drown the roots and attract pathogens and pests into your garden/grow room.


Types Of Pots For Growing Weed

Step 2: Use the Right Germination Techniques

Cannabis seeds need four things in order to germinate: moisture, warmth, darkness, and time. To ensure you grow healthy seedlings, germinate your seeds using one of the following techniques.

🧻Paper towel method

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Mastering The Cannabis Seedling Stage In Just 3 Steps - RQS Blog (4)

Carefully place your cannabis seeds between a few moist pieces of paper towel, and place it all in a plastic container with a lid. Keep the container in a warm, dark place (temperatures between20–25°Care ideal). Leave a slight crack in the lid to allow for some fresh air exchange.

💧 Glass of water method

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Mastering The Cannabis Seedling Stage In Just 3 Steps - RQS Blog (6)

Simply drop your seeds into a glass of water and let them sit in a cupboard for24–48 hours at 20–25°C.Once you see the first signs of taproots sprouting from your seeds, they’re ready to plant. If your seeds don’t germinate after 48 hours in water, switch to the paper towel method. Don’t keep the seeds submerged for more than 48 hours or they’ll rot.

Your seeds are ready to plant once they’ve cracked open and released a small, white taproot. Plant your germinated seeds one knuckle (roughly 3–5 millimetres) deep with the taproot facing down. That way, your seedlings won’t have to reorient themselves.

🦁RQS Starter Kits

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Mastering The Cannabis Seedling Stage In Just 3 Steps - RQS Blog (8)

Alternatively, use the RQS Autoflowering or Feminized Starter Kits to provide your seeds with the perfect conditions from the get-go. This kit contains starter pots filled with perlite and beneficial bacteria, as well as a propagator and lights to breathe life into your seeds.

Step 3: Mastering the Seedling Stage

Now that your seedlings are in their soil, the real challenge begins. Cannabis seedlings are extremely fragile; armed with nothing but frail roots and a small set of cotyledons (that first set of small rectangular leaves), minor stressors can take down your seedlings in just a couple of hours. By taking the time to understand your seedlings and their specific needs, however, you’ll automatically know how to optimise their environment and help them grow into strong vegetative plants.

The Basics: Optimising Light, Temperature, and Humidity for Cannabis Seedlings

Seedlings have very particular needs when it comes to temperature, humidity, and lighting, and missing the mark in any of these areas can prove fatal for such small plants. For best results, we recommend growing seedlings in a propagator where you can easily create the perfect environment for them to flourish in.

🌡️ Temperature

Cannabis seedlings like daytime temperatures of20–25°Cand nighttime temperatures that are roughly 4–5°C cooler. High temperatures will stress your seedlings and stunt their growth, which, at such an early stage, can prove fatal. Dry leaves with curled up edges are a telltale sign of heat stress. With time, your seedlings might also develop other symptoms, including pale foliage and red or purple stems. Heat stress can also cause weak, wilting leaves with downward folding tips.

Cold temperatures, on the other hand, can freeze a seedling’s cells and affect its ability to transport and use nutrients, water, and oxygen. This will result in stunted growth and eventually death if not dealt with properly. Wilting foliage, slow growth, and poor plant turgor are some signs that the temperature in your grow room or propagator is too low.

🌫️ Humidity

While their roots are young and still developing, cannabis seedlings absorb water via osmosis in their leaves. To optimise this process, it’s super important to keeprelative humidity levels at 65-70%.

Humidity levels below 20% will seriously stunt the growth of your seedlings and may cause them to develop symptoms similar to some nutrient deficiencies (yellow or spotted leaves). Humidity levels above 60%, on the other hand, will cause your plants to develop wet spots that can cause foliage to wilt or rot, as well as attract fungi and/or other pathogens and pests. Once your seedlings enter the vegetative phase, you should keep relative humidity at 50%.

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💡 Lights

Seedlings are sensitive to light and will burn under strong HID or LED bulbs. Like adult plants, seedlings will develop burnt, crinkled leaves when suffering from light stress. Alternatively, seedlings that don’t get enough light will grow tall and lanky and topple over.

For best results, we recommend growing yourseedlings under an 18/6 light cycle using CFL bulbswith a blue light spectrum for the first 10–14 days. Once they’ve developed healthy true leaves and at least 2–3 nodes, you can move them under stronger HID or LED lights to start vegging.

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Growing Seedlings Outdoors

Outdoor growers obviously don’t have the liberty of being able to change the temperature or humidity with the push of a button. If you're an outdoor grower, you have three options on how to tackle the seedling stage:

  1. Most growers choose to keep their seedlings indoors under CFL lights for the first two weeks to protect them from elements.
  2. Alternatively, you can keep your seedlings outdoors during the day (as long as temperatures sit consistently between 20–25°C) and only move them indoors at night to protect them from the cold, rain, etc.
  3. Finally, you can keep your seedlings outdoors permanently in a propagator, greenhouse, or polytunnel to provide shelter and allow you to drive up humidity and manipulate the temperature.

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How to Water Your Cannabis Seedlings

How often you should water your cannabis seedlings depends on a variety of factors. The best way to promote the health of your seedlings is to start them off in a high-quality, well-aerated medium. You'll want to grow them in well-draining pots (fabric pots or Air-Pots work best) and, where possible, under standard CFL lights hanging roughly 25–45cm (9–18") from the top of your pots.

The type of grow lights you use, the size of your pots, the exact composition of your soil, and the temperature and relative humidity in your grow room/garden will directly impact how often you should water. Just remember that knowing when and how much water to give each seedling will come with time and practice.

The Best Way to Water Cannabis Seedlings

Cannabis seedlings like warm and moist (but not wet) conditions. During the earliest days of their life cycle, seedlings take up water via their leaves, as their root systems are still underdeveloped.

  1. Mist your seedlings regularly (3–6 times a day, depending on the temperature in your grow area). Be sure to cover your seedlings with a plastic dome or bag to help trap moisture, facilitating their ability to take up moisture via their cotyledons and first true leaves.
  2. Do not water your seedlings directly at the stem. Instead, pour water around the plant in a circle roughly 3cm from the stem. This will promote healthy root growth, as the roots are encouraged to grow outward in search of water, and also prevents moisture buildup at the stem (which can create a breeding ground for Pythium, Botrytis, and Fusarium—fungi that cause "damping off").


How To Water Cannabis Plants: A Comprehensive Guide

When to Water Your Cannabis Seedlings

Remember—there is no universal watering schedule; how and when to water your young plants will vary depending on the factors mentioned earlier. A good rule of thumb is to only water your seedlings when their soil has dried out. You can stick your finger roughly 2cm into the soil to test whether it is dry or not.

When it's time to water your seedlings, it's best to do so early in the morning or just before you switch on your grow lights. This will allow your plant to take up water during the day as it grows. Plus, the warmth from the sun or your grow lights will also evaporate some of the water in your soil, which will help to prevent the buildup of unwanted bacteria and fungi.

How Often Should You Water Your Cannabis Seedlings?

Water your seedlings whenever their soil is dry. This could be every 3–7 days, depending on:

  • The composition of your soil and how much water it retains.
  • The temperature and relative humidity in your grow space.
  • The kind of lighting you are using. CFL and LED lights produce less heat than MH/HID lamps, which tend to dry out soil faster.
  • The size of your pots.
  • How much water you give your seedlings when you water them (see below).

How Much Water to Give Your Seedlings

Again, there is no one-size-fits-all approach to watering cannabis seedlings, and the exact amount of water you give your plants will depend on the size of their pots. In most cases, you won't need to give your seedling more than 1–2 cups of water at a time.

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How to Prevent Damping Off

We’ve all been there; your seedlings look perfectly healthy, then suddenly you find them slumped over the edge of their containers. Within 24 hours (or sometimes less), they’ve shriveled up and died.

This phenomenon, known colloquially as “damping off”, is caused by fungi like Pythium, Botrytis, and Fusarium. While these fungi can lie dormant in soil, they grow and thrive in overly wet conditions. Overwatering and high humidity, for example, are some of the most common causes of damping off.

Unfortunately, by the time your seedlings show the first signs of damping off (a limp and discoloured stem), there’s nothing you can do to save them. We just recommend removing the affected seedlings from your grow room or propagator ASAP to avoid spreading the fungi.

To prevent damping off, make sure to keep close tabs on the temperature and relative humidity in your grow space, and avoid overwatering your plants. Also, make sure both your soil and pots drain well.

Finally, to minimise the chance of a Pythium, Botrytis, or Fusarium infestation even further, be sure to always use new soil orsterilise your soil by baking it in the oven until it reaches a temperature of 85°C.


How To Spot And Prevent Damping-Off

How to Avoid Nutrient Problems

Healthy cannabis plants look vibrant and green, and any sort of discoloration on a plant’s leaves or stems can be a sign of nutrient stress.

Remember, cannabis seeds are jam-packed with nutrients to help get your seedlings through the first stage of their life. Once these nutrients run out, it’s time for you to step in and give your plants the added nutrients they need to veg and flower properly.

1. Feeding seedlings

Cannabis seedlings are super fragile and can easily “burn” in nutrient-rich soil. In general, we don’t recommend feeding during the seedling phase. Instead, keep your seedlings chilling in their Easy Start pots until they’re ready to be transplanted and start vegging.

Most blogs and forums will tell you that your plants are ready to veg after two weeks, but that’s far from true; it usually takes about 3–4 weeks from germination for your seedling to use up all the energy stored in the seed, although some plants develop faster than others. But rather than going by time, we recommend you transplant and start vegging your seedlings once they’ve developed at least three nodes and 4–5 sets of true leaves.

2. Transitioning to the vegetative stage

Once you’ve transplanted your seedlings into their new pots, give them 3–7 days to adjust. Remember, transplanting is a stressful process, and your plants will need some time to recover from it. Feed your plants too early after transplanting, and they likely won’t take up all their nutrients from their medium, which can cause problems (like nutrient lockout) further down the line.

Once you’re confident your plants have recovered from being transplanted, start feeding them with a mild nutrient solution. AnNPK ratio of 4:2:3,for example, is a good starting point for plants just beginning to veg.

3. Nutrient burn

Growers usually run into nutrient burn when they feed their seedlings too early or when they transition into the vegetative phase (either because they transplant their seedlings into hot soil or they start feeding with a fertiliser that’s too strong). The first signs of nutrient burn are dark green leaves with burnt tips. Left untreated, nutrient burn also causes leaves to curl upwards.

Luckily, unlike some of the other seedling issues we’ve mentioned in this post, it is possible to remedy nutrient burn. Simply lay off the nutrients for at least one week and water your plants with plain, pH-balanced water. Once your plant starts to grow more healthy, green foliage, slowly dial the fertiliser back in.

Whenever you start feeding your plants, we recommend giving them half the recommended dose of fertiliser during the first week of feeding. This gives the plants time to adjust to their new diet.

4. Going organic

At RQS, we’re big fans of organic cannabis gardening. No amount of chemical nutrients could ever compare to the complex mix of microorganisms that exist in organic soil.

When growing organic, the focus is all about building a vibrant soil from the get-go, rather than growing in a stagnant medium and pumping it full of chemical nutrients once a week. While it’s a lot more hands-on, the taste of organic weed is hard to beat. Just remember that organically grown plants typically don’t provide the same yields as their non-organic siblings.

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How to Prevent Pests and Bugs

Pests and plagues can destroy seedlings in less than a day. To prevent this from happening, it’s super important to keep the environment around your seedlings clean and at optimal temperatures and humidity levels. Avoid overwatering, and remember to read up on common cannabis pests so you can spot and treat them early. Some common pests to look out for include:

1. Fungus gnats

These small, black, fly-like bugs feed off your plants and lay their larvae in wet topsoil.

2. Spider mites

Black or red in colour, spider mites live on the underside of leaves and sometimes spin protective webs around healthy foliage. They love hot, dry conditions.

3. Leaf miners

These small, slender, winged insects leave irregular snail-trail-like spots on healthy leaves.

4. White powdery mildew

As the name suggests, white powdery mildew is a type of mould that forms as a white, flour-like powder on the leaves of your plants.

5. Pythium and Fusarium

These fungi can be hard to spot, but white spots on wet topsoil can be an early sign of their presence.

Cannabis seedlings like warm, humid conditions. Unfortunately, pests and diseases also love these conditions. Keeping things extra clean and growing your seedlings in a propagator can help prevent an infestation.

How to Prevent Stretchy Seedlings

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Seedlings stretch in order to get closer to their light source. To keep your seedlings from developing unnaturally long, flimsy stalks, grow them underblue spectrum CFLs located roughly 5cm from the top of the plants.Also, avoid keeping your seedlings in the dark for 24 hours after germination (a common piece of advice on grow forums), as the lack of light will force your seedlings to stretch abnormally.


How to Prevent and Fix Stretching in Cannabis Seedlings

Know When and How to Transplant Your Seedlings

Unfortunately, transplanting seedlings is far from an exact science; rather than following a strict calendar or schedule, it’s all about paying attention to your plant and knowing which cues to look out for.

As we mentioned earlier, a good rule of thumb is to transplant seedlings when their leaves fully cover the circumference of their container. After about one week, try checking on your seedlings’ roots. If you can completely remove a seedling and all its soil, it is ready to transplant.

Remember to be very gentle when handling your seedlings and transplanting them. Any minute damage to their roots can result in a ton of stress that, for such young and fragile plants, can take a while to recover from.

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Bonus Step: Understanding the Seedling Stage

Inside that dark, hard shell, cannabis seeds house all the necessary genetic information to sprout and grow into big, luscious plants. When exposed to humidity and warmth, seeds are able to absorb water from their environment. This process is known as imbibition, and it’s the key to life for all plants.

Once water enters a seed, it activates special enzymes that trigger the growth of the taproot (the small white root that pops out of seeds when germinated properly). This root starts to push deeper underground in search of more water while the seed sends a shoot up and out of the soil in search of light.

Cannabis seeds already contain two cotyledons (or embryonic leaves) that unravel and push the seed casing from the shoot. After the cotyledons emerge, cannabis plants will develop their first set of true leaves. These will grow out of the main stem and have just one finger.

During the early stages of their lives, cannabis seedlings get all their energy from stores inside the seed. As their roots develop, they can absorb water via their leaves. Once your plants have developed their first sets of true leaves (that is, leaves with at least 5–7 fingers), they are no longer considered seedlings and are officially vegging.

Remember, rapid growth and vibrant green foliage are telltale signs of healthy seedlings.

Get Growing!

Now that you know the theory behind growing healthy cannabis seedlings, it’s time to get your hands dirty. Remember to invest in one of our Starter Kits for the best, most reliable results, and keep reading our blog for more tips on growing spectacular weed at home.

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How long does the seedling stage take cannabis? ›

Plants are considered seedlings for about 2-3 weeks after germination. During this time, the plant should be moved to a spot with direct sun, if growing outdoors. If growing indoors, set your grow lights to run for 16 hours a day. After the seedling stage, Cannabis plants move to a vegetative stage.

What helps cannabis seedlings grow? ›

Soil is the most natural way to germinate your cannabis seeds, and its high moisture content makes it quite easy to do. Soil also contains minerals and microbes that help the plant develop. The temperature of the potting soil also makes it the best growing medium.

What should a 3 week old cannabis seedling look like? ›

Cannabis Seedling stage (2 to 3 weeks)

This is how the seedling stage begins: when the seed opens, the first pair of small round leaves that appear, are called “cotyledons”. After that, the small Cannabis plant starts to produce serrated leaves, not the characteristic digitated leaves, only single serrated leaflets.

How much should I water my cannabis in seedling stage? ›

As per watering frequency, cannabis plants, especially young, require watering every two to three days, a little less often in the germination and seedling stages when the water usage is lower.

How deep should a cannabis seedling be? ›

The short answer for cannabis seed planting depth is 0.5 to 1.5 inches (1.3 to 3.8 centimeters) deep. However, if you're growing cannabis plants in a pot, it's best to pick a reasonable depth for the space. Keep reading for additional insights into how deep to plant cannabis seed now.

How often should I water seedlings? ›

Seedlings should be watered once a day or every other day, depending on how much sun and heat they get. Remember that seedling roots are fairly close to the surface and they're growing in a small amount of media, so they don't need a deep soak the way larger plants do.

Should I mist my cannabis seedlings? ›

Cannabis seedlings like warm and moist (but not wet) conditions. During the earliest days of their life cycle, seedlings take up water via their leaves, as their root systems are still underdeveloped. Mist your seedlings regularly (3–6 times a day, depending on the temperature in your grow area).

How do I make my seedlings stronger? ›

To strengthen seedlings, introduce a light wind with an oscillating fan. Don't put it on full blast, but enough to create gentle shaking and movement. Movement helps the stems of leggy seedlings become more tough and strong. Tickling seedlings with your hands can help in the same manner.

What makes seedlings grow faster? ›

Thus, feeding the plants with water that has CO2, helps the plants to grow rapidly and greener. Carbonated water contains many macronutrients such as oxygen, hydrogen, phosphorus, carbon, potassium, and sodium; all of which are advantageous for the growth of plants.

How much darkness do cannabis seedlings need? ›

The plants need at least sixteen hours of light during the seedling stage, but eighteen is best with six hours of darkness. During the seedling stage, the LED blue light spectrum is preferred. Moist soil, high humidity, and eighteen hours of the LED blue light spectrum will ensure the rapid growth of cannabis.

What do overwatered cannabis seedlings look like? ›

The sure way to identify overwatered cannabis plants is by inspecting the soil. A mushy appearance and texture indicate that the growing pot is clogged from top to bottom. You can also do a quick test using a soil moisture meter to check the presence of water saturation deep in the growing pot.

Is it better to overwater cannabis seedlings or underwatered? ›

The wilting of underwatered cannabis is different from the plump curling of overwatering - even if only subtly. Leaves will be fragile, brittle and even papery. They will look lifeless and drab. Another sign of an under watered cannabis plant an extremely dry growing medium, such as crispy soil.

Do you water cannabis seedlings everyday? ›

Seedling stage-How often to Water Cannabis

Simply test whether the soil is damp by putting your finger into the soil to see if has dried out. If you are growing in a pot, you'll likely find that you need to water every 3-7 days. This also depends on the size of the container.

What are healthy cannabis seedlings? ›

At the seedling stage, Cannabis plants are very sensitive and vulnerable, their root system is not yet developed and they need special care, little watering, and humidity. A healthy seedling has a short stem and green leaves. Remember to take notes about this stage and monitor your environmental factors.

Should you give cannabis nutrients every watering? ›

Typically, every other watering should be accompanied by liquid nutrients. That means 1-2 times a week is a healthy dosage.

How do you tell the difference between healthy and unhealthy cannabis seedlings? ›

Identifying healthy vs unhealthy cannabis seedlings

An unhealthy cannabis seedling may have yellow or discoloured leaves. You may also find that your cannabis seedling is not growing. To the experienced eye, the unhealthy cannabis seedling simply doesn't look the same as the normal healthy looking seedling should.

What temperature do cannabis seedlings like? ›

Young growing cannabis plants prefer temperatures between 75 and 80 degrees Fahrenheit. Anything above 80 degrees Fahrenheit is not recommended.

How strong should light be for cannabis seedlings? ›

For best overall results, BIOS recommends that you grow your seedlings under an 18/6 light cycle using Icarus LED lamps, set 24-36 inches from the leaf canopy, and under a blue light spectrum for their first 10-14 days. 18/6 simply means 18 hours of light and 6 hours of darkness.

Should you mist seedlings? ›

Many indoor seeds and seedlings will do well with a light mist from a spray bottle. This might have to be done every day (or even twice each day) since it only waters the surface and does not sink into the soil. Once the seeds have germinated and started leafing out, they may require heavier watering.

Should I spray water on seedlings? ›

Once your seedlings have germinated, it's important to keep watering them consistently and gently for the first few weeks. Young seedlings are very susceptible and can easily be knocked over by a strong water stream. For this reason, I recommend using either a hand pump sprayer or a spray bottle.

How do I know if my seedlings have enough water? ›

Feel the Soil

The surest way to detect dry soil is by feeling the top half-inch of soil or seed starting mix. If the soil is dry and easily movable, your seedlings need water! If the soil feels wet and dense, your seedlings are good for now.

What do cannabis seedlings do at night? ›

During the dark cycle, cannabis plants are not photosynthesising, and continue to respire at a constant rate; they do not just begin to respire when the lights go out. The Calvin Cycle, which is light-independent, processes all that stored up solar energy into carbohydrates.

Is sunlight good for cannabis seedlings? ›

Cannabis plants are happiest when they get between 10–12 hours of direct sunlight per day. As you'll likely have witnessed with your own eyes, weed plants grow really vigorously, and hence need a ton of solar energy to fuel their growth.

Do cannabis seedlings like full sun? ›

Sunlight. Weed requires 6 to 12 hours of daylight. Growing a plant in the shade is not a good option as marijuana needs direct sunlight.

When should I take the dome off my seedlings? ›

DO remove the plastic humidity dome after your seeds germinate. Domes are really only used on the trays until the seeds germinate, which for some varieties may be as few as a few days. Once your plants have popped up, they need lots of air and light. Left on too long, domes can kill seedlings.

What to do when seedlings get big? ›

What to do when your seedlings grow too big
  1. Pot up. ...
  2. Fertilize. ...
  3. Take off the flowers. ...
  4. Water when the soil starts to dry out. ...
  5. Watch out that the tops of the plants don't hit the lights. ...
  6. Harden off the plants. ...
  7. Just go ahead and plant them.
May 6, 2022

What do seedlings need most? ›

Seedlings should be fertilized after they are three inches tall and can be fertilized weekly after that until transplanting. All plants need nitrogen (N), phosphorus (P) and potassium (K), which are commonly stated on fertilizer bags as whole numbers, such as 2-2-3.

Does baking soda help plants grow? ›

Baking soda on its own can't be used to fertilize plants, but you can use it with other products to make a good replacement for Miracle Gro garden fertilizer. Just combine 1 tablespoon of epsom salt with a teaspoon of baking soda and a half teaspoon of household ammonia.

What causes weak seedlings? ›

The most common cause of legginess is an insufficient or uneven access to light. When the light source is too dim or distant, seedlings grow quickly in height to get closer to that light. As the seedling gains height, it sacrifices in girth and strength, resulting in thin, pale, fragile, stretched-out stems.

What color are healthy cannabis seedlings? ›

Cannabis plants are treated as seedlings until they develop leaves with a full number of fingers. Healthy seedlings should be short with thick vegetation and their leaves should appear vibrant green in color.

Is too much light bad for cannabis seedlings? ›

However, if your plants receive too much light, they may experience unhealthy growth, wilting, and even burning. It is important to adjust the light intensity for different stages of growth.

Does cannabis grow more at night? ›

Cannabis in the vegetative stage (when it is growing at a rapid pace) needs at least 13 hours of light per day. In fact, indoor growers commonly use an 18/6 light to dark ratio to encourage faster growth.

What does an overfed cannabis plant look like? ›

Likewise, if your plants show signs of burnt tips, browning tips, or if the leaves become crispy and curl up these can all be signs of overfeeding.

Can you over water cannabis seedlings? ›

So, technically, overwatering means you're depriving your plants of oxygen. When the roots of plants are soaked, any oxygen will be quickly consumed. Without enough oxygen for the roots your plants will go into oxygen deprivation and the leaves will start to turn, droop, curl, engorge, and the plant will die.

Is rain water good for cannabis seedlings? ›

Rain and spring water

It speeds up the growth of plants, does not have an excess of salts, and overall has the optimal amount of nutrients. Many growers note this water makes cannabis plants bloom more abundantly and for a longer time.

What do underfed cannabis plants look like? ›

As mentioned above, marijuana plants will begin to look like they are underfed. The plants themselves will start to pale in color, and look stunted. Leaves on affected plants will be fragile, and root growth could also be stunted.

Is bottom watering better for seedlings? ›

Bottom watering seedlings is a better method, so the seeds don't get dislodged by the force of the water coming from above. Just make sure that the water reaches the top of the soil, or the seedlings may not germinate.

What is the best time of day to water cannabis plants? ›

Watering during the morning, for both indoor and outdoor grows, appears to be the most suitable. This gives plants ample food and water for the day, and means that once the cool, dark night comes around, the soil is not too wet.

Are darker cannabis seeds better? ›

Healthy marijuana seeds are dark brown, black, or some combination of both. We'd recommend you don't use green seeds. Green seeds usually aren't yet mature enough to sprout. Both bigger and smaller seeds will work.

Can cannabis seedlings get too much nutrients? ›

Nutrient burn, also known as "nute burn," is a common problem when growing cannabis. When cannabis plants receive too much fertilizer, they can't absorb all of the nutrients they need, and the excess can build up in the leaves and cause the leaves to turn yellow or brown and become crispy.

How big should a 2 week old cannabis seedling be? ›

Many growers consider the first 2-3 weeks after germination to be the cannabis seedling stage. These are the first couple of weeks where the seedling is most vulnerable. The seedling may only be a few inches/cm tall with a couple of sets of true (non-cotyledon) leaves.

Is it better to water cannabis at night or day? ›

Many experienced growers agree that the best time to water the cannabis is around 9 a.m. or in the evening. If you water cannabis at lunchtime, the sun simply evaporates a significant part of the moisture even before it completely penetrates the soil and feeds the root system.

How much water does a cannabis plant drink a day? ›

On average, the researchers found, a cannabis plant consumes an estimated 22.7 liters, or 6 gallons, of water per day during the growing season, which is typically 150 days long from June through October.

How many times a week should I feed my cannabis? ›

Feed frequency: As a rule-of-thumb, generally feed once per day, or once every other day. To determine if plants are ready for feeding, lift the pot (or slab) to check if it feels light. Alternatively: For soil, only feed once the soil feels dry up to about 1 inch (25mm) below its surface.

How long do seedlings take to appear? ›

Seeds generally germinate somewhere between 7 and 21 days after sowing. During this period it is important to keep the soil moist but not wet. If the soil dries out then the seeds will probably fail to germinate. The first two leaves of the seedling that appear are not 'true' leaves but are called cotyledons.

How many days does it take for a seedling? ›

Germination usually takes at least a couple of weeks, but can take up to a couple of months. Different species show varying germination times. Generally sprouts in 2-6 weeks. Will take much longer if soil temperature is cool.

What should my Cannabis seedling look like after 2 weeks? ›

How Big Should My Weed Plants be After 2 Weeks? In most cases your plant should be around 2 to 3 inches tall with 2 to 3 sets of leaves including the cotyledons (seed leaves which are rounded).

How long is each stage of the Cannabis plant? ›

Photoperiod seedlings need to grow for 4-6 weeks before they are ready to flower. Clones are mature when they root and can be planted densely in a sea of green and transitioned to flower right away. Most strains flower for 8 or 9 weeks, so an indoor grower could pull 5 or 6 harvests per year in a perpetual system.

What is the success rate of seedlings? ›

Experimental planted seedlings. The mean survival of seedlings planted in our experiment after three growing seasons (2017–2019), across species, was 20 %. Piñon seedlings had the highest survival after three years at 36 %, followed by ponderosa pine at 25 %, southwestern white pine at 11 % and Douglas-fir at 10 %.

Can you make seedlings grow faster? ›

If you're trying to grow something very quickly, you'll want to use a liquid fertilizer. If you're growing something over a long stretch of time, use a granular fertilizer. Granular fertilizers are coated in a resin that slowly releases nutrients into the soil over time.

How soon do seedlings need light? ›

The answer to this one is simple. Your grow lights should be turned on (or your seedlings should be put under lights) as soon as the first seed starts to sprout. Many types of seedlings grow very fast, and they will begin reaching for the light as soon as they emerge. So give them plenty of it right from the start.

How do you start seedlings faster? ›

Damp paper towels, napkins and coffee filters can all be used to germinate seeds, or even test if seeds are viable—just place seeds on a damp paper towel, place in a plastic bag and store in a cool, dark place to encourage rapid growth. Once the seedlings sprout, transfer them into loose potting soil.

How many years does it take for a seedling to grow big enough to be sold as a Christmas tree? ›

Grass is planted in the fall, and the trees get planted in early spring. From there, it takes about 6-8 years for the trees to grow to a marketable height.

What is after seedling stage? ›

Basic Facts. The average plant goes through four stages: seed, sprout, seedling, adult plant.

How many nodes before topping? ›

It is recommended that you wait until your plants have at least four nodes before topping them, and most growers recommend topping the plant above the sixth node. Nodes are the part of a plant that connects new stem offshoots with older growth, which can form a branch, a leaf, or in the case of cannabis plants, a bud.


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